Vacuum cleaner



Jan. 12, 1960 R. DESCARRIES VACUUM CLEANER Filed April 1, 1958 4Sheets-Sheet 1 FIG./

Jan. 12, 1960 R. DESCARRIES 2,921,153

1 VACUUM CLEANER Filed April 1, 1958 4 Sheets-Sheet 2 INVENTOR fa /4MUZICKL fix; ATTORNEY Jan. 12, 1960 R. DESCARRIES 2,921,153

VACUUM CLEANER Filed April 1, 1958 4 Sheets-Sheet 4 A; ATTORNEY UnitedStates Patent F VACUUM CLEANER Raymond Descarries, Montreal, Quebec,Canada, assignor to Aktiebolaget Electrolux, Stockholm, Sweden, acorporation of Sweden Application April 1, 1958, Serial No. 725,726

15 Claims. Cl. 200-50 My invention relates to suction cleaners.

It his already been proposed to provide a control to open an electricalswitch and disconnect a motor-fan unit of a suction cleaner from asource of electrical supply when a cover at the air inlet end of thecleaner, which may, be hinged thereto, moves from its closed position.

An object of my invention is to provide an improved control of this typeto open an electrical switch of a suction cleaner andstop its operationwhen the cover at the air inlet end thereof moves from its closedposition, which is of simplified construction.

Another object of the invention is to provide in a horizontal-typesuction cleaner, having a casing provided with two top portions atdifferent levels and a sloping wall portion therebetween, an improvedcontrol of this type which can be readily assembled and in which theparts are accurately aligned.

A further object of the invention is to provide an improved electricalswitch having a pivotally mounted operating member which effectivelyremains in its on or off positions when moved to either position and canbe effectively employed in a control of this type for controlling theoperation of a suction cleaner.

Further objects and advantages of the invention will become apparent asthe following description proceeds, and the features of novelty whichcharacterize the invention will be pointed out with particularity in theclaims annexed to and forming a part of this specification.

For a better understanding of the invention, reference may be had to thefollowing description taken in connection with the accompanyingdrawings, in which:

Fig. l is a side elevational view of a suction cleaner embodying theinvention;

Fig. 2 is a top plan view of the cleaner illustrated in Fig. 1;

Fig. 3 is an enlarged side elevational view of the cleaner shown in Fig.1, partly broken away and in section, to illustrate parts more clearly;

Fig. 4 is a fragmentary top plan view, partly broken away and insection, of the cleaner shown in Fig. 3;

Fig. 5 is an enlarged fragmentary sectional view of parts illustrated inFig. 3 to illustrate details;

Figs. 6 and 7 are enlarged fragmentary vertical sectional views taken atlines 6-6 and 77, respectively, of Fig. 4;

Fig. 8 is a vertical sectional view taken at line 88 of Fig. 6;

Fig. 9 is a horizontal sectional view taken at line 99 of Fig. 8;

Fig. 10 is an enlarged fragmentary horizontal sectional view taken atline 10-10 of Fig. 3;

Figs. 11 and 12 are vertical sectional views taken at lines 11-11 and1212, respectively, of Fig. 10;

Fig. 13 is an enlarged fragmentary vertical sectional view taken at line13-13 of Fig. 10;

Fig. 14 is a fragmentary vertical sectional view taken at line 14- 14 ofFig. 13; and

2,921,153 Patented Jan. 12, 1960 ICC Fig. 15 is an enlarged verticalsectional view taken at line 1515 of Fig. 10.

Referring to the drawings, I have shown my invention embodied in ahorizontal tank-type suction cleaner 10 comprising a casing 11, a frontend cover 12 and rear end cover 14. The casing is provided with a handle15 and wheels 16 and 17 to facilitate movement thereof on a supportingsurface, the wheels 17 being at opposing sides of the casing and thesingle caster wheel 16 at the front end of the casing being disposedbetween the side walls of the cleaner.

The front end cover 12- is formed with an inlet 18 to which a suctionhose (not shown) is adapted to be removably connected. Suitable cleaningtools may be connected to a wand which in turn is connected to the outerfree end of the suction hose and through which air flows into the frontend of the casing by a suitable motor-fan unit 19 disposed therein. Dirtentrained in air drawn into the inlet 18 is separated from air when itpasses through a dust collecting member 20, and air from which dirt hasbeen removed is discharged from the casing 11 through an opening (notshown) in the rear end cover 14.

End rings 21 and 22 are fixed to the front and rear ends, respectively,of the casing 11. The front end ring 21 is provided with a U-shapedgroove 23 about the periphery thereof which receives the front orforward edge of the casing 11, as best shown in Figs. 6 and 7. A

suitable sealing gasket 24 is provided in the groove about the extremeedge of the casing 11 to provide an air-tight joint. At the top of thecleaner 10, between the opposing sides thereof, the front end ring 21 isprovided with a raised part 21a at which region it is secured at 25 toan angle bracket 26 fixed to the top of the casing 11. The front endring 21 also may be secured in any suitable manner (not shown) to thebottom part of the casing 11.

The bottom of the front end cover 12 is pivoted at 27 to the front endring 21 and suitable latching mechanism is provided for latching the endcover to the casing 11.

As best shown in Fig. 5, the latching mechanism includes a latch member28 pivotally mounted on a pin 29 fixed within the front end cover 12,and a latch keeper 30 in the form of a pin extending between spaced lugs31 projecting forward from the front end ring 21.

The latch member 28 may be formed of sheet metal and provided with alatching detent or catch 32. A hairpin spring 33 surrounds the pivot pin29 at the side of the latch .member 28 with one leg 34 engaging thelatch member and the leg 35 engaging a stop 36 in the cover 12. Thus,spring 33 yieldingly rocks the latch member 28 toward latching position.

A lug 37 extends upwardly from the latch member 28 between the pivot pin29 and catch 32 and projects into an opening 38 in the front end cover12. A push button 39 is mounted on the lug 37 for manually pressing thelatch member against the action of spring 33 to an unlatching position.Latching member 28 also has a depending arm 28a which may be connectedto other parts (not shown) in the end cover 12 in such a manner that,whenthe push button 39 is released and the spring 33 becomes effectiveto rock the latch member 28 counterclockwise, such upward rockingmovement will be arrested .to position the cam surface 40 on the nose ofthe latch is described and illustrated in my copending applicationSerial No. 725,730, filed April 1, 1958.

The rear end ring 22, which is suitably fastened to the rear end of thecasing 11, is provided with a U-shaped groove 41 about the peripherythereof which receives the rear edge of the casing, the latter beingembedded in suit-" able sealing material 42 to provide an air-tightjoint, as shown in-Figs. 11, 12 and 13.

As best shown in Fig. 3, the top of casing 11 includes two portions atdiflerent elevations which are joined by a sloping wall portion. A trimstrip 43, which conforms to the top of the casing 11 and includes twosections at dilferent elevations, extends lengthwise of the casing top.

The higher level section of the trim strip 43, whichiis of invertedU-shape, is provided with an elongated slot 44 at the region of a switch45 and an opening 46 at its juncture with the sloping portion. The outerend of the lower trim strip section is provided with an opening 47 atthe vicinity of thefront end cover 12.

Between the openings 46 and 47 in the trim strip 43 to form asmooth-walled pocket 48 directly opposite the handle 15; The handle 15desirably is formed of a material, such as a suitable plastic, forexample, to provide a hand. grip which essentially keeps its shape andyet is slightly flexible and resilient in character to facilitate itsnals 71 and 72, and another conductor indicated at 73 in Fig. 10, tocomplete a circuit across the contact fingers Y 69 and 7% for themotor-fan unit when theswit-ch operating member'64 is moved to close theswitch contacts62 and 63.

The switch 45 t is clamped tightly between the top of the casing 11 andthe underside of the trim strip 43 by the tightening screws 50 and 51The switch operating member 64 projects upwardly through the elongatedslot 44 in the trim strip, the underside thereof at the peripheral edgeof the slot having a shoulder 74 engaged by the top thetop surfacethereof .is depressed and of concave shape connection to, the trim strip43. The forward end 15a I of the handle 15, which is essentially square,is formed with a shoulder 49 which fits snugly about the underside ofthe periphery of the trim strip opening 47. The

. front and rear walls 15b and 15c of the forward end 154 of the handle15 rest against the bracket 26 and top wall of the casing 11, as shownin Figs. 6and 7.

The rear end 15d of the handle 15 extends intothe,

' trim strip opening 46 and is provided with side ledges 15e,

edges-of the walls 59 and 60 of the switch receptacle 57. This leaves aslight clearance 75 for the lugs 66 in the notches 65 atthe sides 59 ofthe receptacle 57, so that the. switch operating member 64 will see-sawand rock backand forth freely about its 'fulcrurnWhen it is moved to.closeand open thecontacts 62 and 63,-of the switch 45.

.As bestishown .in Fig. 1 2, thescrew 51 passes through apertured partsof the element 67 andthe right-hand portion-of the iswitch part 54 forfirmly securing these parts :tothe casing 11. A part of the element-67,which is formed. .of suitable insulating material, projects beyond the.end of the trim strip 43.

one of "which is shown in Fig. 3. The side ledges 15a engage innersurface portions of the trim strip at the vicinity of the opening 46 andanchor the rear end 15d of the handle to the trim strip 43.

The raised part 21aof the front end ring 21, which is of invertedU-shape and serves as a front extension'of "The, rearend cover 14isprovided with a pair of spacedapartarms .or bracketsat the bottomthereof which projectdownwardly and also toward the casing 11, one

of which is indicated at 76 in Fig. 1. The lower ends of the. -.arms .76are pivoted on the rear end of the casing 11 in any-suitable manner(:not shown) for rocking movement about .an'axis below the bottom of thecasing. Re-

the trim strip 43, is formed with a rearwardly extending lip 21bacrossthe top and both sides thereof, as illustrated in .Figs. 6, 7 and 9. Theforward edge of the trim strip 43 is provided with a shoulder 43a whichengages the front end ring lip 21b, the extreme forward edge of the trimstrip being positioned within the lip to anchor and lock the front endof the trim strip to the casing 11. After the front end of the trimstrip 43 is locked in position to the front end ring 21 in the-mannerjust ex- .ferring to Figs. .2 and 3, a latch 77 is provided at the top.of the rear end cover 14 for releasably latching the end cover at therear end of the casing 11.

A cover plate 78 for the rear end cover 14, having a Y central opening79 therein, nests within the open end of plained, the trim strip can befastened to the casing 11 I by screws '50 and 51. I

The electric switch 45' is provided at the top of the casing 11 forcontrolling the supply of electrical energy through conductors 52 and53to the rnotor-fan unit19, as shown in Figs. 11 and 12. The switch 45comprises, a part 54 formed of insulating material, the extremelefthand' and right-hand ends of which are indicatedat 55 and 56,respectively, in Figs. 11 and '12. The left-hand;

portion'of part 54 provides an open-top receptacle 57 of. rectangularshape having a bottom 58 and upstanding side and end walls 59 and 60,respectively, for housing an insulating member 61 upon which are mountednormally open stationary and movable switch contacts 62 and 63,,

respectively. The contacts 62and 63 are actuated by a manually operablemember 64 having a top wall formed of two lever arms or sections whichslope upwardly from a central region of the member.

The side walls 59 of the receptacle 57 are formed with notches 65 havinground bottom portions for fulcruming the outwardly extending lugs 66 ofcircular form provided at the opposing side walls of the switchoperating member 64. With this construction, the member 64 is angularlyif movable within the receptacle 57 about an axis coinciding with that ofthe lugs 66, the opposite end walls of the the cover and may be securedthereto by a number of screws, oneof which is indicated at in Figs. 11and 12. The cover plate 78 and rear end ring 22 are closely adjacent toone another when the rear end cover '14 is closed, as seen in Figs. 12and 13, and a suitable sealing gasket (not shown) may be provided at 81about the periphery of therear end ring 22 to provide an air-tight sealbetween these parts. As seen in Fig. 12, a filter pad 82 may bepositioned in the space between the end cover 14 and rear end ring 22which may be provided with a transverse apertured wall. 83.

Referring to Fig. 1, an opening 84 is formed in a side wall of the rearend cover 14 through which is adapted to pass an electrical cord (notshown) having a conventional connecting plug 85 at the end thereof,which arrests inward movement of the cord through the opening, Asuitable cord reel, a side wall 86 of which is illustrated in Fig.13,:may be provided for the electricalcord within therear end cover 14from which electrical connections may extend to a pair of slip rings 87and 88 which are provided incircular grooves in the reel side Wall whichis formed of suitable insulating material.

The cover plate 78 for the rear end cover is formed of suitableinsulating material, such as plastic, for example, which includes an armor projecting part 89 at the top part thereof having a pair of recessedportions, one of which is indicated at 90in Fig. 13. The part 89 forms aterminal block having resilient clips 91 in the recessed portionsthereof which are engaged by the contact fingers v 69-ahd 70 when therear end cover 14 is latched to the casing 11 and the cavity 68 receivesthe terminal block 89." To the resilient clips 91 are connecteddownwardly resilient leafsp'rings 92and 93 having contact buttons attheir lower ends which are in good intimate contact with the slip rings87 and 88, respectively.

Cord reel structure mounted in a rear endcover of a horizontal tank-typesuction cleaner, and of a type which can conveniently be employed in thepreferred embodiment being described is illustrated and described in mycopending application Serial No. 725,732, filed April 1, 1958'. Suchcord reel structure includes a reel, having a side wall like the wall 86illustrated and described, with resilient leaf springs for completingthe electrical connection from the inner end of the electrical cord to aterminal block at the top of the rear end cover. If desired, referencemay be made to my aforementioned application for a description of thecomplete cord reel structure, the disclosure of which may be consideredto be incorporated in this application.

As best shown in Figs. 11 and 15, a short lever arm 94 is adjacent toand extends downwardly from one of the lugs 66 and moves over the outersurface of a side wall 59 of the switch receptacle 57. The lever arm 13,whose length is less than one-half of that of the lever arms or sectionsof operating member 64 which extend in opposite directions from the lugs66, is also angularly movable about these lugs. The bottom pointed endof the lever arm 94 is arranged to ride over a bump 95 formed in a leafspring 96 whoseends are held in notches 97 formed in a side of theswitch part 54. After the lever 94 rides over and depresses the bump 95in the leaf spring, the latter flexes upward sufficiently to hold theswitch operating member .64 to the position to which it has just beenmoved.

In the preferred embodiment being described, the switch 45 is arrangedto open the contacts 62 and 63 and disconnect the motor-fan unit 19 fromthe source of electrical supply when the front end cover 12 moves fromits closed latched position. Mechanism for opening the switch 45responsive to opening of the end cover 12 includes an elongated rod 98formed of wire which extends lengthwise of the casing from the switch 45to the front end cover 12 and includes two substantially straightsections at different levels which are joined by an inclined section atthe region of the top sloping wall portion of the casing 11, as shown inFig. 3. The lever arm 94, at a region removed from its axis of rockingmovement, is apertured to receive a bent end portion 98a of the rod 98,as best illustrated in Fig. 15.

The rod 98 is closely adjacent to the top of the casing 11 and isconcealed from view by the inverted U-shaped trim strip 43 whichoverlies the rod. The end of the rod 98 at the front end of the casing11 passes through an elongated slot 99 formed in a pin 100 and is bentback upon itself to form a hook 101, as shown in Fig. 6. The pin 100 isaxially movable in a hollow sleeve 102 which forms a unitary part of andmay be formed integrally with the top part 21a of the front end ring21and projects rearwardly therefrom.

The hollow passage in the sleeve 102 is of greater diameter than the pin100 about which is disposed a helical spring 103, one end of which bearsagainst an apertured collar or ring 104 which is tightly fitted withinthe rear end of the hollow sleeve 102 and through which the pin 100extends. The opposite end of spring 103, which is maintained undertension in the hollow sleeve 102, bears against a washer 105 fixed at106 to the pin 100. The raised part 21a of the front end ring 21 isapertured at 107 to provide a passage through which the pin 100 projectsforward from the front end of the casing 11 When the front end cover 12is latched in its closed position, a part 108 within the cover engagesthe forward end of the pin 100 and moves the latter rearwardly withinthe hollow sleeve 102 against the tension of the spring 103.: With thefront end cover 12 closed and the switch 45 open, which is indicated bythe solid line position of the switch operating member 64 in Figs. 11and 12, the rod 98 moves toward the front end cover 12 and the hookedend 101 assumes the solid line position illustrated in Fig. 6. Assumingthat the front end cover 12 continues to remain in its closed position,the operating member 64 of switch 45 can be shifted to its dotted lineposition in Figs. 11 and 12 to move contact 63 upward and close thecontacts 62 and 63 to complete the circuit for the motor-fan unit 19.When this occurs, the rod 98 is moved .rearwardly by the lever arm 94and the hooked end 101 thereof is shifted to the dotted line position inFig. 6. The slot 99 at the rear end of pin 100 is of sufiicient lengthfor the hooked end 101 of rod 98 to move from its solid to its dottedline positions in Fig. 6 while the front end cover remains in its closedposition.

If the latch push button 39 in Fig. 5 should now be depressed to releasethe catch 32 from the pin 30, the spring 103, which is under tension,becomes operable to move the front end cover sufficiently to lose thesuction at the end cover and the latter will fall forward by gravityabout the pivotal connection 27. When this occurs. the part 108 in thefront end cover 12 will no longer be effective to engage the front endof pin 100, the cover being in a position out of reach of the pin, asindicated by the dotted line position of the cover in Fig. 6, whereuponthe spring 103 will become effective to move the pin forward and movethe rod 98 so that the hooked end thereof will move from the dotted lineposition to the solid line position in Fig. 6. Under these conditions,the rod 98 will exert a forward pull on the lever arm 94 and move theswitch operating member 64 from its dotted line to its solid line'position in Figs. 11 and 12 and automatically open switch 45.

Also, when the front end cover 12 is latched in its closed position, asillustrated in Fig. 6, the switch operating member 64 may be moved atwill to close and open switch 45, the relative position of the slot 99and hooked end 101 of rod 98, and the length of the slot, being suchthat the switch operating member can be manually moved to the switchopen position when the front end cover is closed or moved automaticallyfrom the switch closed position to the switch open position responsiveto movement of the front end cover latch to its release position.

While a particular embodiment of the invention has been shown anddescribed, such variations and modifications are contemplated as fallwithin the true spirit and scope of the invention, as pointed out in thefollowing claims.

I claim:

1. In a suction cleaner having an inlet and an outlet fOr air andelectrically operable means for moving air therethrough, a wall memberforming an exterior wall of the cleaner, the wall member having anopening, means including an electrical switch having an operating membermovable between on and off positions for controlling the electricallyoperable means, means for mounting the switch in the cleaner with atleast a part of the operating member projecting through the opening andaccessible exteriorly of the cleaner, means for pivoting the operatingmember for see-saw movement about a fulcrum intermediate the endsthereof, the operating member having first and second lever armsprojecting in opposite directions from the fulcrum which forms an axisabout which the arms are angularly movable, the operating member havingan element which forms a unitary part thereof and is disposed at theinner side of the wall member, the element forming a third lever armwhich is angularly movable about the axis and whose length is less thanone-half of that of said first and second lever arms and disposedtherebetween, a stop in the path of movement of the third lever arm forholding the operating member to either one of its positions to which itis moved, and structure for yieldingly supporting the stop so that itwill yield and move out of the path of movement of the third lever armresponsive to movement imparted to the operating member.

2. A suction cleaner as set forth in claim 1 in which the structure forsupportingthe stop comprises resilient means. I

3. A suction cleaner as set forth in claim 2 in which the resilientmeans comprises a bowed leaf spring,

4. A suction cleaner as set forth in claim 5 in which the stop ispositioned intermediate the ends of the bowed leaf spring.

5. A suction cleaner asset forth in claim 1 in which the structure'forsupporting the stop comprises a leaf spring, the stop beingdisposedintermediatethe ends of the bowed spring and pr'ojecting from theconvexside thereof.

6. A suction cleaner as set forth in claim lin which the switchoperatingmember intermediate its ends is provided with outwardlyextending parts, means at the inner side of the wall member forpivotally supporting the outwardly extending parts for angularly movingthe operating member about the axis intermediate the ends thereof, thestructure for yieldingly supporting the stop including a bowed leafspring, the stop comprising a bump provided at the convex side of theleaf spring intermediate the ends thereof, and the stop normally beingsupported in the path of movement of the outer end of the third leverarm.

7. A suction cleaner as set forth in claim 6 in which the structure foryieldingly supporting the stop includes a pair of walls having notcheswhich receive the ends of the leaf spring and are spaced apart adistance less than that of the spring when fiat;

8. In a suction cleaner having an inlet and an outlet for air andelectrically operable means for moving air therethrough, a wall memberforming an exterior wall of the cleaner, the wall member having anopening, an open-top receptacle having a bottom and side wall, means tosupport the receptacle at the inner side of the wall member with theside wall thereof engaging such inner side at the peripheral edgeof theopening, means including an electrical switch having an operating membermovable between on and off positions for controlling the electricallyoperable means, means for mounting the switch in the receptacle, theoperating member at a region intermediate its ends having projectingparts at opposing sides thereof, the side wall of the receptacle beingnotched at the open end thereof to receive the projecting parts toprovide 'a fulcrum, the operating member projecting through the openingand being accessible exteriorly of the cleaner, the operating memberhaving first and second lever arms projecting in opposite directionsfrom the fulcrum about which the arms are angularly movable, theoperating member having an element which forms a unitary part thereofand is disposed at the inner side of the wall member, the elementforming a third lever arm which is angularly movable about the axis andwhose length is less than one-half of that of said first and secondlever arms and disposed therebetween, a stop in the path of movement ofthe third lever arm for holding the operating member to either one ofits positions to which it is moved, and structure for yieldinglysupporting the stop so that it will yield and move out of the path ofmovement of the third lever arm responsive to movement imparted to-theoperating member.

9. A suction cleaner as set forth in claim 8 which includes a casing, anelongated member of inverted U-shape extending lengthwise of the casingwith the side walls thereof extending upward frorn'the top of the casingand the closed end thereof forming a ridge, the ridge forming theexterior wall of the cleaner having the opening through which theoperating member projects, means to support the receptacle at the top ofthe casing within the elongated member, .the receptacle having a basewhich extends beyond at least one side of the receptacle tov leaf:spring positionedin the gap, the stop comprisinga bump provided at theconvex side of the bowed leaf spring;

;10; Asuetionfcleaner as set forth in claim 9 in which the portionof thebase in the gap is provided with spaced apart notches to receive thebowed leaf spring.

11. A suction cleaner as set forth inclaim 10 in which the thirdleverarm is always in'contact with the bowed, spring in either its on oroif positions or in any positonrtherebetween,

. 11- 2. snct'ioncleaner as set forth inrclaim 11 in which the stopcomprises an intermediatebent section of the bowed leaf spring. 1

13. -I n- .a horizontal-type suction cleaner having an open-ended casingand apertured front and rear end covers therefor providing an air inletand an air outlet, respectively, and electrically operable means formoving air therethrough, an end ring fixed to the air inlet end of thecasing, means for positioning the front end cover on the end ring, meansincluding an. electrical switch having an operating member removablefrom the front end cover which is angularly movable between on and offpositions for manually controlling the electrically operable means,means for pivoting the operating member for angular movement about anaxis intermediate the ends thereof, the operating member having anelement which is angularly movable therewith, and control means operableto move the operating member from its on to its off position responsiveto movement of the front end cover from its closed position,

the control means comprising a pin, the end ring being apertured toreceive the pin, resilient means to bias the pin to project it forwardfrom the end ring when the. front end cover opens, the pin being movablerearward against the action of the biasing means upon closing the frontend cover, the rear end of the pin having an elongated slot extendinglengthwise of the casing, an elongated member having its rear endconnected to the angularly movable element at a fixed region removedfrom the axis about which the operating member is angularly movable, thefront end of the elongated member having a hook connected to theelongated slot in the pin, and the hook and slot connection being soconstructed and formed that the pin imparts forward movement to theelongated member responsive to movement of the front end cover from itsclosed position only when the switch operating member is in its onposition.

14. A suction'cleaner as set forth in claim 13 in which the top wallofvthe casing is provided with adjoining sections at different levelswhich extend from the opposite ends of the casing toward a regionintermediate the ends thereof and a sloping top wall sectiontherebetween, the switch being disposed at the higher level section ofthe casingand the pin being disposed at the lower level section of thecasing, and the elongated member connected to the angularly movableelement of the switch operating member and to the elongated slot of thepin having a sloping section intermediate the ends-thereof at thevicinity of the sloping top wall section.

15. In a horizontal-type suction cleaner, an opencnded casing andapertured front and rear end covers therefor providing an air inlet andoutlet, respectively, and electrically operable means for moving airtherethrough, an end ring fixed to the air inlet end of the casing, theend ring having a raised top part of inverted U-shape, means forpositioning the front end cover on the end ring, the top wall of thecasing having adjoining sections at different levels which extend fromthe opposite ends of the casing toward a regionintermediate the endsthereof and a sloping top wall section therebetween, an. elongated stripwhich conforms to the shape of the top 9 wall and is disposed over bothtop wall sections at different levels and the sloping wall sectiontherebetween, the elongated strip being of inverted U-shape with itssides extending upward fromthe top wall of the casing and its closed endforming a horizontally disposed ridge between the opposing sides of thecasing, the elongated strip at its forward end at the lower levelsection abutting the raised top part of the end ring and conforming tothe shape of the latter, means including an electrical switch having anoperating member angularly movable between on and off positions formanually controlling the electrically operable means, means for pivotingthe operating member for angular movement about an axis intermediate theends thereof, the operating member having an element which is angularlymovable therewith, the ridge having an opening at the higher levelsection of the top wall, the operating member projecting upwardlythrough the opening and being accessible exteriorly of the casing andthe angularly movable element being disposed within the elongated strip,and control means operable to move the operating member from its on toits off position responsive to movement of the front end cover from itsclosed position, the control means comprising a pin, the raised top partof the end ring being apertured to receive the pin, resilient means to10 bias the pin to project it forward from the end ring when the frontcover opens, the pin being movable rearward against the action of thebiasing means upon closing the front end cover, an elongated memberextending Within the elongated strip from the rear end of the pin to theangularly movable element, the elongated member having a sloping sectionintermediate the ends thereof conforming to the sloping top wall sectionof the casing, and means for connecting the front and rear ends of theelongated member to the rear of the pin and to the angularly movableelement, respectively, the last-mentioned connecting means being soconstructed and arranged that the switch operating member is manuallymovable from its on to off position and vice versa when the front endcover is closed and is also movable from its on to its off position bythe control means responsive'to movement of the front end cover from itsclosed position.

References Cited in the file of this patent UNITED STATES PATENTS1,775,320 Rattay Sept. 9, 1930 2,737,262 Ferraris Mar. 6, 1956 2,814,358Beede et a1. Nov. 26, 1957

